Environmentalists have designed an entire neighborhood of sustainable homes and businesses, complete with solar-powered office buildings and a wind energy center, to replace the aging GenOn coal-fired power plant on Alexandrias waterfront.

Problem is, it isnt for sale.

The American Clean Skies Foundation, which promotes natural gas and other non-coal energy sources, released a 67-page document Wednesday proposing a $450 million project aimed at retiring the plant in favor of a district that would put Alexandria at the center of the new energy economy. Anchored by an energy museum and business center, Potomac River Green as its been dubbed would add $27 million to city coffers over 10 years and create 2,200 jobs, according to the report.

Its a rosy proposal consistent with the citys longstanding wish to oust an industrial resident that has failed to meet air quality standards in the past. Potomac River Green would augment Alexandrias reputation as an eco-city, too, officials said.

But Pepco owns the land and GenOn still has 89 years left on its 100-year lease.

The fact is that the plant is operating and the company has made no announcements relating to a potential future shutdown, so until that time a plan or pictures or diagrams of what could be there is premature and fantasy, said GenOn spokeswoman Misty Allen.

ACSF is banking on a commissioned study by Alexandria-based Analysis Group, a utility research firm that found the plant contributes little to the regions power grid about 5 percent. A Pepco spokesman said another study, by PJM Interconnection, is currently underway to determine the plants necessity.

ACSF President Gregory Staple believes a shutdown delivers an out to GenOn and its stockholders, who could lose money as the 60-year-old facility tries to keep up with increasingly stricter environmental regulations.

We think this is a market-based, business-friendly solution to an end-of-life scenario thats tough for everyone, Staple said. [GenOn] may view us as unhelpful but were providing an economic reality check which I think a public company cant ignore.

The threat of coal plants losing money as environmental standards rise is real, Allen said. Energy producers around the country including GenOn are analyzing their ledgers to make sure theyre getting a return on investment.

But politics will likely play a role in any decision relating to retiring coal generating stations. Future presidential administrations and Congress can always reverse the trend of stricter regulations.

There is a lot of regulatory uncertainty right now Congress could take money from the EPA in the future, Allen said.

The alternative is that the federal government could fix a sharper eye on coal plants, Alexandria City Councilman Rob Krupicka said.

Krupicka and City Councilwoman Del Pepper, who have repeatedly berated the plants existence in a dense residential area, attended NCSFs presentation last week at the National Press Club. Krupicka welcomed the proposal as a conversation starter if nothing else. Alexandria could be left with hazardous plot of land if GenOn ceased operating and the city was unprepared, he said.

I think its appropriate to ask questions about what comes next but understand theres going to be a lot of work to shutting this plant down, Krupicka said.

The Potomac River Green proposal calls for the new district to be completed by 2018. Krupicka would not comment on whether the timeline was realistic, but said any land-use issue in Alexandria would require extensive time, work and public input.

The plan is flexible a starting point, according to Staple.We put out this plan to catalyze the discussion about the future, he said.

Allen said GenOn officials have no reason to meet with American Clean Skies until they have a developer or financing plan.